Unfortunately, my entire stay at AC Hotel Sunnyvale Cupertino was frustrating and unpleasant.At check-in, even though I had already prepaid for my reservation, I was asked to pay another $498. If I hadn't caught the mistake, I could have ended up paying twice.The breakfast situation was even worse. I had booked and paid for a stay that included breakfast, yet I had to argue with the front desk repeatedly throughout our two-night stay just to receive what I had already paid for.On our first morning, the front desk flat-out told me that breakfast was not included. Only after I showed my confirmation email did the employee say, as though she were doing me a favor, that she had added breakfast for that day. She then told me to email my confirmation to the manager and check with the front desk again each morning.That evening, I specifically confirmed that breakfast was included for all three of us, including our child. I was assured that everything was taken care of. Yet the next morning, we were told that breakfast was only included for two adults. Once again, I had to go back to the front desk and argue about something I had already paid for.Even the breakfast itself was disappointing. You could order one breakfast item, but the additional breakfast bar had very limited options. Despite having prepaid, we were also presented with a bill showing what our breakfast would have cost if ordered separately. After all the hassles we had already experienced, this felt like unnecessary pressure to leave a tip.The final interaction at checkout perfectly summed up our stay. I noticed some cookies and politely asked if we could have one. I was told they were only for Marriott Gold members. When I explained that we actually were Gold members and hadn't received any welcome cookies, the employee answered the phone and simply waved her hand at us to go away. It was incredibly rude and dismissive.What bothered me most wasn't just the repeated mistakes. It was the unfriendly attitude and the way we were treated whenever we tried to resolve them.I paid for a hotel stay expecting a comfortable, hassle-free experience, not to spend every morning at the front desk proving what was included in my reservation.From check-in to check-out, this was an extremely disappointing experience. I would not stay here again.

After a very poor experience at Sonesta ES Suites Sunnyvale, I moved to AC Hotel Marriott Sunnyvale Cupertino — and what a difference.I keep coming back to this hotel, and I will definitely return again. The service is excellent, the staff is warm and attentive, everything is clean and well maintained, and the breakfast is delicious.A consistently great experience. Looking forward to coming back soon!

Located on the famous El Camino Real highway in Silicon Valley. Marriott properly describes this facilities with adjectives like: elegant, sophisticated, and stylish. And I concur with that description. My quarrel is with the layout of the room. It is supposedly a European-style open concept design, The toilet, shower, and sink/vanity have no doors or walls which separates those areas from the bedroom. So there is no privacy in using the restroom faciilties.It may be trendy but its not me.

UPDATED REVIEW (TripAdvisor makes you delete the original review and repost). Special thanks to the Assistant GM (Pele) for personally calling me to apologize and to discuss our experience. Now that's great customer service! I am completely satisfied with the outcome of our conversation and the actions taken by Pele to rectify the issues, including staff training.Below is my original review: AC Hotel Sunnyvale CupertinoSunnyvale, CaliforniaSuper thin walls!December 2025I've been a Marriott member for many years. This hotel has the most paper thin walls and front entry door I've ever experienced. No problems if you're flanked by quiet neighbors adjacent and across from your room. Unfortunately for us, the persons across from our room brought a young dog that would cry/whimper every 5 min. I, along with other neighboring rooms, called the front desk numerous times, and security finally intervened around midnight. In the morning our next door neighbors were extremely loud (talking and laughing) starting at 6:45 am! And unfortunately, any hallway noise is super amplified, so needless to say we had a rough night. Not sure why a modern hotel doesn't have better sound proofing.Besides the noise levels the hotel is fine otherwise. But FYI, management is not very empathetic to legitimate complaints.

I've been a Marriott member for many years. This location has thee most paper thin walls and front entry door I've ever experienced. No problems if you're flanked by quiet neighbors adjacent and across from your room. Unfortunately for us, the persons across from our room brought a youg dog that would cry/whimper every 5 min. I, along, with others called the front desk numerous times until nearly midnight for them to properly address. And our next door neighbors were extremely loud (talking and laughing) starting around 6:45 am! And anything happening in the hallway is super amplified. Not sure why a modern hotel doesn't have better sound proofing.Besides the noise levels the hotel is fine otherwise. But FYI, management is not very empathetic to legitimate complaints.